It’s probably not going to snow this weekend, but snow lovers in Washington shouldn’t lose all hope. Some forecast models are now advertising the potential for a winter storm Monday night into Tuesday.
But snow lovers shouldn’t get too excited either, as other models are not keen on much if any snow from the Monday night storm system.
First things first: The storm that models previously predicted to bring snow Saturday night and Sunday will be pushed so far south by an Arctic air mass building into the region that little or no precipitation is likely to fall.
Despite the lack of snow this weekend, it will be much colder than normal, with highs mostly in the 30s.
The forecast gets interesting again Monday night into Tuesday. A disturbance dropping out of Canada toward the Mid-Atlantic may combine with a developing wave of low pressure off the North Carolina coast. Some models are forecasting the explosive development of a coastal storm when this merger occurs that would hammer the interior Mid-Atlantic and New England with heavy snow.
However, some models predict the Canadian disturbance will pass north of Washington and wait to develop into a more powerful storm until it reaches New England. In this scenario, the Washington area would receive little or no snow.
“There is a ton of uncertainty with the Monday night storm possibility,” said Wes Junker, Capital Weather Gang’s winter weather expert. “This could be a major storm, but there’s also a lot of support for it not doing a whole lot.”
We see three plausible scenarios:
1. Storm mostly misses to north: We’d have a chance of rain or snow showers as it curled away from us Monday night into Tuesday, but accumulating snow would be unlikely.
2. Major storm: The Canadian disturbance would phase with a coastal wave off the North Carolina coast and turn into a powerful storm. Heavy precipitation would fall, although the storm may draw enough warm air inland that snow could mix with or change to sleet and rain along and east of Interstate 95. Substantial snow amounts would be likely in the interior Mid-Atlantic in this scenario.
3. Minor storm: The Canadian disturbance would pass near or to the south of the region and bring a period of light to moderate snow but not turn into a monster coastal storm.
It is too soon to say which of these three scenarios is most likely.
The European model, which is generally the best performer, favors the non-stormy scenario 1. However, a few of the 51 simulations that make up its ensemble (group of simulations with small tweaks to the data feeding them) predict accumulating snow in Washington and something resembling the stormy scenario 2. All together, the European ensemble simulations indicate about a 10 percent chance of at least one inch of snow in Washington on Monday night and Tuesday:
The Canadian model, the worst performer, has been gung-ho in predicting the stormy scenario 2. The GFS model, which is in the middle of the pack, has alternated between scenarios 2 and 3.
The simulations that make up the GFS ensemble (known as the Global Ensemble Forecast System, GEFS) show a mix of possibilities from snow to rain, to a rain-snow mix, to no precipitation at all:
Given all of this conflicting information, it’s best to stay tuned. For snow lovers, all hope is not lost — at least, not yet.